When you shoot while cloaked your energy goes down and the nanosuit can't keep you cloaked. When the trainer is active and the energy is kept at 100% the energy won't go down and the nanosuit can keep you cloaked.But you can reduce to 1/sec the cloak's energy consumption even while sprinting by editing this row in one of the difficulty cfg files:g_suitCloakEnergyDrainAdjuster = 0